from django.shortcuts import render
from django.http import HttpResponseRedirect,Http404
from django.core.urlresolvers import reverse
from django.contrib.auth.decorators import login_required

from .models import Topic,Entry
from .forms import TopicForm,EntryForm

# Create your views here.

def index(request):
	"""学习笔记的主页"""
	return render(request,'learning_logs/index.html')

@login_required
def topics(request):
	"""显示所有主题"""
	topics=Topic.objects.filter(owner=request.user).order_by('date_added')
	context={'topics':topics}
	return render(request,'learning_logs/topics.html',context)

@login_required
def topic(request,topic_id):
	"""显示单个主题下面的所有笔记"""
	topic=Topic.objects.get(id=topic_id)

	# 确认请求的主题属于当前用户
	if topic.owner != request.user:
		raise Http404

	entries=topic.entry_set.order_by('-date_added')
	context={'topic':topic,'entries':entries}
	return render(request,'learning_logs/topic.html',context)

@login_required
def new_topic(request):
	"""添加新主题"""
	if request.method != 'POST':
		#为提交数据，创建一个新表单
		form=TopicForm()
	else:
		# post提交数据，对数据进行处理
		form=TopicForm(request.POST)
		if form.is_valid():
			new_topic=form.save(commit=False)
			new_topic.owner=request.user
			new_topic.save()

			return HttpResponseRedirect(reverse('learning_logs:topics'))

	context={'form':form}
	return render(request,'learning_logs/new_topic.html',context)

@login_required
def new_entry(request,topic_id):
	"""在指定的主题中添加新条目"""
	topic=Topic.objects.get(id=topic_id)

	if request.method != 'POST':
		#为提交数据，创建一个新表单
		form=EntryForm()
	else:
		# post提交数据，对数据进行处理
		form=EntryForm(data=request.POST)
		if form.is_valid():
			new_entry=form.save(commit=False)
			new_entry.topic=topic
			new_entry.save()

			return HttpResponseRedirect(reverse('learning_logs:topic',
				args=[topic_id]))

	context={'topic':topic,'form':form}
	return render(request,'learning_logs/new_entry.html',context)

@login_required
def edit_entry(request,entry_id):
	"""编辑既有条目"""
	entry=Entry.objects.get(id=entry_id)
	topic=entry.topic

	if topic.owner != request.user:
		raise Http404

	if request.method != 'POST':
		#为提交数据，创建一个新表单
		form=EntryForm(instance=entry)
	else:
		# post提交数据，对数据进行处理
		form=EntryForm(instance=entry,data=request.POST)
		if form.is_valid():
			form.save()

			return HttpResponseRedirect(reverse('learning_logs:topic',
				args=[topic.id]))

	context={'entry':entry,'topic':topic,'form':form}
	return render(request,'learning_logs/edit_entry.html',context)